Is my builder’s quote too expensive? How to test the price

A high building quote may reflect a complicated job, a fuller scope, a longer programme or a builder who cannot take the work cheaply. A low one may omit expensive items. Test what the price buys before deciding whether it is too expensive. The goal is a credible cost for the same completed project, not simply the smallest headline figure.

Make the scope comparable

Put the drawing revisions, specification and schedule of works beside the quotation. Identify what is included, excluded, provisional and client supplied. Check design, structure, scaffold, site protection, drainage, services, finishes, waste, inspections and making good where relevant to your project. An allowance for a bathroom suite is different from an allowance for the complete fitted bathroom.

If you have other quotes, compare the same scope and responsibilities line by line. Our guide to comparing builders’ quotes shows why a gap can be a difference in work, not just price. If the design is incomplete, the builders may be pricing different assumptions.

Test the delivery plan

Ask how many people will work on the project, for how long, and what specialist subcontractors are included. Look at access, occupation, weatherproofing, long lead items and sequencing. A quotation that implies one small crew will finish a complex extension in an implausibly short period may be more worrying than a dearer one with a credible programme.

Consider the cost of the whole project, including fees, client purchases, contingency and temporary arrangements. The builder’s contract sum is only one part of the homeowner’s budget. Our extension budget guide explains the distinction.

Use benchmarks carefully

Published square metre ranges can provide an early sense check, but often describe different finishes, regions, dates and inclusions. Do not multiply an internet figure by your floor area and call it a fair tender price. A measured cost plan based on the actual design, quantities and construction method provides a stronger test. The RICS New Rules of Measurement offer an established framework for cost planning and measurement.

Ask the builder to explain unusual items and qualifications rather than demanding an arbitrary discount. If the price is above budget, identify which design choices or specifications could change, and understand the effect before removing work. A cheap change during tender can cause more expense later if it leaves an unresolved detail.

Decide whether to proceed

A useful review produces a comparison on common scope, a list of missing information, a cost range that reflects uncertainty and a sensible next step. At early design stage, Build Advocate’s Cost & Readiness Assessment tests budget and delivery risk. If builders have been shortlisted, Complete Builder Selection examines their quotes, programme, due diligence and proposed appointment together.